Contralateral C7 nerve transfer for severe pediatric brachial plexus injuries: donor site morbidity

Background Pediatric brachial plexus injuries (BPI) can have a devastating impact on upper extremity function. With localized lesions, nerve grafting and transfers are well-described. However, reconstruction of pan-plexus (C5-T1) injuries (PPI) requires donor nerves outside of the brachial plexus. The cross C7 (CC7) nerve transfer extended with sural nerve grafts to the contralateral recipient nerve offers the advantage of supplying robust donor axons. Though controversial in the West, CC7 transfer is routine in many Asian centers. We present a case series of pediatric patients who underwent CC7 transfer for BPI. Our objective was to catalog donor site morbidity incurred by transferring the C7 nerve root. Methods This retrospective study was approved by the Institutional Review Board of our university. Inclusion criteria: patients under 18 years old that underwent CC7 nerve transfer for BPI at our health system between 2021 and 2022. A chart review was completed to collect demographic and outcomes data. Results Three patients underwent a complete CC7 transfer between 2021 and 2022 for BPI reconstruction. All patients underwent concomitant additional nerve transfers. Post-operative donor site sensory deficits were minimal and transient in all but one patient, who reported mild but persistent paresthesia of the donor side hand with movement of recipient side digits; however, no patients suffered donor site motor deficits (Table 1). Conclusions We conclude that CC7 nerve transfer is a safe surgical option to provide additional donor motor axons for PPI in pediatric patients.